Sequence preceding the core-dump:
0) Dovecot2 was locked:
$ pkg lock mail/dovecot2
1) Dovecot2 was merged into dovecot:
$ pkg set -o mail/dovecot2:mail/dovecot
$ pkg set -o mail/dovecot2-pigeonhole:mail/dovecot-pigeonhole
2) I required the latest repos instead of the quarly one (unrelated: since my custom ports running on latest tree where failing) thus created:
cat <<EOF /usr/local/etc/pkg/repos/FreeBSD.conf
FreeBSD: {
url: "pkg+http://pkg.FreeBSD.org/${ABI}/latest"
}
EOF
3) Did a fetch of new repos details:
$ sudo pkg upgrade
4) Attempted upgrade fails. The traceback/logging is from the 2nd attempt, since first one was no longer present in my framebuffer. Error message is the same, yet missing some lines about the (already downloaded) new repository.
$ sudo pkg upgrade
Updating FreeBSD repository catalogue...
FreeBSD repository is up to date.
All repositories are up to date.
...
dovecot2-2.2.30.2_1 is locked and may not be modified
Processing candidates (133 candidates): 100%
Checking integrity...
dovecot2-2.2.30.2_1 is locked and may not be modified
Assertion failed: (cun != NULL), function pkg_conflicts_check_chain_conflict, file pkg_jobs_conflicts.c, line 481.
Child process pid=2637 terminated abnormally: Abort trap
I know this is a rather odd sequence of events and I have not tried to reproduce it, yet it might be interesting to one may concerned.
FYI: As a workaround I unlocked mail/dovecot and did the upgrade.